1) Wiley offers a way to group metric by URL. However the default configuration puts all the values in to one category called default. I found the following set of configuration groups them my application context and then my urls.
The above configuration works well, except it leaves the '/' in the url. I have not figured out how to get rid of it yet.
Wily uses property files for most configuration. Even though they look like java properties file, they do not support line break. ie you cannot use "\" at the end of the line to split the value of a property across multiple lines.
Is there any difference between multiple metric tracer and single metric tracer?
No significent performance improvemnet on the agent. But, the EM will perform better as it has less data to process. Also, it helps with the limit of 200K metric per agent limit.
Multiple dashboards with different security privilige
You can create different domains and assign dashboards to those domains and controluser access at the domain level. This gives a nice way of eliminating complexity of the UI for users who do not have to see all the dashboards.